TuBULiPoiiA. Z. ASCIDIOIDA. 269 



mentientem exhibuerunt," Pallas. Orkney and Shetland islands, 

 Jameson. 



Polypidom adherent by a narrow base, calcareous, of a faint pur- 

 ple colour or white, depressed, irregularly divided, the segments flat, 

 bifid, spreading, more or less revolute, obtuse, the under surface even 

 and striate, the upper rough with the tubulous cells arranged in trans- 

 verse rows, but divided by a central groove, which winds along the 

 branches : the cells are generally placed in close apposition, some- 

 times they are disjunct, and the walls are minutely frosted. — The 

 entire polypidom rarely exceeds half an inch in length. 



Milne-Edwards is of opinion that the T. serpens of O. Fabricius 

 is not synonymous with the Linnaian species, but with the T. fim- 

 briata of Lamarck, in which opinion a re-perusal of the description, 

 in the Fauna Gro?nlandica, does not induce me to coincide. Milne- 

 Edwards refers our polypidom to the genus Aulopore. Ann. des Sc. 

 Nat. Part. Zool. viii. 331. 



3. T. TRUNCATA, " stem round, branched, ending icith enlarg- 

 ed globular heads, radiated with plates of united vertical cells." 

 Jameson. 



Tubulipora truncata, Flem. Br. Anim. 329 Millepora truncata? Ja- 

 meson in Wern. Mem. i. 560 T. tronque, Blainv. Actinol. 425. 



Hab. " In deep water, Zetland," Dr Fleming. Shetland Islands, 

 Jameson. 



" About an inch in height, the branches scarcely exceeding one- 

 eighth ; the branches are short, pierced by numerous pores, the open- 

 ings of cells converging towards the centre ; the head is stellate, the 

 rays are highest in the middle of their course, diminishing towards 

 the centre and lower margin of the head ; each ray is compressed, 

 and consists of two rows of tubular cells, united, crowded, with sub- 

 angular orifices ; the tubes have a central direction, and give to the 

 sides of the plates a striated appearance. This species has probably 

 been referred to as an inhabitant of the north seas, under the title 

 of Millepora truncata,* but it differs widely from the Myriozoos of 

 Donati, to which the term was restricted by Pallas." Fleming. 



* * * Crustaceous. (Obeli a, Lamouroux.) 

 4. T. Obelia, crustaceous, the cells in rows, tubular, icith an 

 oblique even rim. Miss Elliot. 



Plate xxxi. Fig. 7, 8. 



* Stew. Elem. ii. 426, pi. 12, fig. 7- 



